The vacuum quality of cryogenic liquid containers that use a vacuum between an outer wall and an, inner cryogenic liquid container wall are typically tested by filling the cryogenic liquid container with a specific liquid product. The inner cryogenic liquid container typically has a portion thereof filled with the liquid and a gas area filled with the product in a gaseous state at a pressure selected either by the selection of or the adjustment of gas vent valve that has a vent inlet into a top of the gas area of the inner cryogenic container to prevent the pressure within the gas area from exceeding the set or selected value. With the gas vent valve remaining in the open condition, the cryogenic liquid container is then allowed to reach thermal equilibrium, usually by waiting a period of time between twelve and twenty-four hours. The cryogenic liquid container is then physically lifted onto a scale, usually by a fork lift or gantry crane, to obtain an first container weight (the weight of the cryogenic liquid container and the weight of the liquid product remaining after the liquid product within cryogenic liquid container reaches thermal equilibrium). The cryogenic liquid container is then removed from the scale and placed in a stable ambient temperature environment for several days with the gas vent valve in the normal open condition. After several days, the cryogenic liquid container is placed back on the scale and a second weight is obtained (the weight of the container and the weight of the liquid product within the cryogenic liquid container that has not evaporated during the period the cryogenic liquid container remained in the stable ambient temperature environment for several days). The NER is then determined in pounds per day loss of the liquid product by subtracting the second weight from the first weight and then dividing the result by the number of days between the first weight measurement and the second weight measurement. The determined pounds per day loss, NER, of the liquid product is then compared against a vacuum quality interpretation scale to determine the vacuum quality of the cryogenic liquid container. Because the above described typical method takes a long time and often requires the use of expensive lifting equipment to lift and move the cryogenic liquid container multiple times, it would be desirable to have a simple, less expensive, safe method for rapidly and reliably determining the pounds per day loss value used to obtain the NER of the liquid product as well as the vacuum quality of the cryogenic liquid container.